Silicon optoelectronic device using silicon nanowire and method for preparing the same

Abstract

The present invention relates to a silicon optoelectronic device using silicon nanowire and a method for preparing the same. More particularly, the present invention relates to a silicon optoelectronic device using silicon nanowire, which is prepared by doping erbium (Er) into silicon nanowire and form a silicon dioxide sheath on the surface of the silicon nanowire by oxidation, so that the diameter of the silicon nanowire is reduced to give quantum confinement effect and photoelectric transition effect, and a method for preparing the same. When an electric current is applied, light emitted by the photoelectric transition effect of the silicon nanowire excites and decays the doped erbium to effectively emit light having a wavelength of about 1.5 μm. The silicon dioxide sheath effectively amplifies the light by the microcavity effect of the silicon nanowire.

1 . A silicon optoelectronic device comprising 
 a) an n-type or p-type semiconductor substrate;    b) silicon nanowire which is formed on one side of the substrate and is rendered conductive by a p-type or n-type dopant and erbium;    c) an insulating film which is formed on the substrate and encloses the silicon nanowire;    d) a first electrode which is formed on the silicon nanowire, a part of which has been exposed by etching, and enables electrical connection of the silicon nanowire; and    e) a second electrode which is formed on one side of the substrate and enables electrical connection of the exposed silicon nanowire and the substrate.    
     
     
         2 . The silicon optoelectronic device of  claim 1 , wherein the substrate is made of Si, SiC, GaN or GaAs.  
     
     
         3 . The silicon optoelectronic device of  claim 1 , wherein the dopant is B or P.  
     
     
         4 . The silicon optoelectronic device of  claim 1 , wherein the silicon nanowire is enclosed by a silicon dioxide sheath.  
     
     
         5 . The silicon optoelectronic device of  claim 1 , wherein the silicon nanowire has a diameter of less than 10 nm.  
     
     
         6 . The silicon optoelectronic device of  claim 1 , wherein the silicon nanowire enclosed by the silicon dioxide sheath and acts as microcavities.  
     
     
         7 . The silicon optoelectronic device of  claim 1 , wherein the insulating film is made of polymer, SiO 2  or Al 2 O 3 .  
     
     
         8 . The silicon optoelectronic device of  claim 1 , wherein the first and second electrodes are Ti/Au, Al or ITO (indium tin oxide) transparent electrodes.  
     
     
         9 . A method for preparing a silicon optoelectronic device comprising the steps of 
 a) depositing Au on an n-type or p-type semiconductor substrate and flowing a silicon-containing precursor on the substrate at 400-1,000° C. to form silicon nanowire;    b) doping a p-type or n-type dopant and erbium or a precursor thereof into the silicon nanowire to offer conductivity;    c) oxidizing the silicon nanowire at 300-1,000° C. to form a silicon dioxide sheath on the surface of the silicon nanowire;    d) forming an insulating film on the substrate, on which the silicon nanowire has been formed, enclosing the silicon nanowire;    e) etching the substrate to expose a part of the silicon nanowire; and    f) forming a first electrode and a second electrode to enable electrical connection of the substrate and the exposed silicon nanowire.    
     
     
         10 . The method for preparing a silicon optoelectronic device of  claim 9 , wherein the erbium precursor is ErCl 3 .  
     
     
         11 . The method for preparing a silicon optoelectronic device of  claim 9 , wherein the doping of erbium is performed by adding erbium or an erbium precursor during the formation of the silicon nanowire.  
     
     
         12 . The method for preparing a silicon optoelectronic device of  claim 9 , wherein the doping of erbium is performed by a method selected from the group consisting of wet method, sol-gel method, coprecipitation, chemical deposition, laser abrasion and sputtering using erbium or an erbium precursor after the silicon nanowire has been formed.  
     
     
         13 . The method for preparing a silicon optoelectronic device of  claim 9 , wherein the etching of the substrate is performed by wet etching or dry etching.